This section introduces aspects that may help facilitate a better understanding of the invention. Accordingly, the statements of this section are to be read in this light and are not to be understood as admissions about what is prior art or what is not prior art.
Power amplifiers are used in many applications to amplify electronic signals. For example, power amplifiers are used to amplify electronic signals for broadcast in cellular communications systems, where the electronic signals contain data streams for multiple different users. Depending on the time of day, the electronic signal may contain data streams for different numbers of users. For example, the number of nighttime users may be significantly smaller than the number of daytime users. Typically, the operating power level of such a communications system is proportional to the number of users.
In a typical cellular communications system, a power amplifier may be designed and configured to operate efficiently at maximum traffic levels to provide a gain on the order of 40 dB for an output power of about 10 Watts. Unfortunately, during minimal traffic levels having an output power of 4-5 Watts, that power amplifier will operate less efficiently with higher levels of undesirable DC consumption.